Peers in the House of Lords have been left stunned following the shock resignation of international development minister Lord Bates.

The former MP stepped down from his post after apologising for being late to oral questions in the House.

The Conservative minister was due to answer questions at the start of a debate on income inequality but was late, which forced Lords Chief Whip Lord Taylor to answer instead.

He said: "My Lord, with the leave of the House, I wonder if you would permit me to offer my sincere apologies to Baroness Lister for my discourtesy in not being in my place to answer her question on a very important matter at the beginning of Questions.

"During the five years it's been my privilege to answer Questions from this despatch box on behalf of the government, I've always believed that we should rise to the highest possible standards of courtesy and respect in responding on behalf of the government to legitimate questions of the legislature.

"I'm thoroughly ashamed at not being in my place and therefore I will be offering my resignation to the Prime Minister with immediate effect."

Peers on both sides of the Lords were left stunned as he promptly walked out of the chamber.

Shortly after he walked out Labour peer Baroness Smith insisted Lord Bates had no reason to resign for for the "minor discourtesy"

In his role at the International Development department, his areas of responsibility included the overseas British territories as well as the United Nations.